There is a continuing desire in the microelectronics industry to increase the circuit density in multilevel integrated circuit devices, e.g., memory and logic chips, thereby increasing their performance and reducing their cost. In order to accomplish this goal, there is a desire to reduce the minimum feature size on the chip, e.g., circuit linewidth, and also to improve the properties of the interposed layer of dielectric material to lower the dielectric constant and avoid cracking of the dielectric layers during manufacturing of the integrated circuit device.
One prior art dielectric material used in integrated circuit devices is a slurried particulate glass which is coated as a film on a substrate and sintered to form the dielectric layer. Unfortunately, sintering requires very high temperatures which are unsuitable in some applications. A solution of methyl silsesquioxane is sold by Allied Signal Corp. under the trademark AS-418 for use as a dielectric material in microelectronics. A solution of hydridosilsesquioxane is also sold by Dow Corning Corp. under the Trademark FO.sub.x for use in microelectronics. However, films of silsesquioxane, especially thicker films which are required for dielectric layers in microelectronics, have a tendency to crack during manufacturing. There is a continuing need in the art for a low dielectric composition which can be readily formed into thick films and processed without cracking.
It is therefore an object of the present invention to provide an improved dielectric composition and process for forming the dielectric layers in integrated circuit devices.
Other objects and advantages will be apparent from the following disclosure.